Mono, di and polyfunctional cyclic imino ether compounds and various polymerization products thereof are known, for example, from U.S. Pat. Nos. 1,958,529; 4,490,771; 3,630,996; 4,628,102; 4,005,746; 3,639,395; 3,763,177; 3,784,508; 3,822,237; 3,730,915; 4,652,620; 4,430,491; 4,484,143; 2,556,791; 2,504,951; 2,562,113; 3,402,178; 3,312,714; 3,268,544; 3,198,806; 3,247,220; 2,929,836; 3,108,114; 2,811,529; 2,889,351; 2,876,232; 3,432,600; 3,453,284; 3,161,650; 3,278,382; 2,831,858; 2,897,182; 3,248,397; 3,367,895; 2,569,428; 3,419,520; 2,252,200; 3,458,456; 3,438,943; 3,738,961, and 4,245,063. J. M. Rodriguez-Parada and V. Percec, Journal of Polymer Science, Part A: Polymer Chemistry, volume 25, number 8, pages 2269-2279 (1987) report on the polymerization of three monooxazolines containing a mesogenic moiety to produce poly(N-acylethylenimine)s. Said cyclic imino ethers produce a range of polymerization products which possess useful physical and mechanical properties, however, improvement in their properties, would be highly desireable.
The present invention provides a method for improving one or more of the physical and mechanical properties, such as thermal stability, glass transition temperature, chemical resistance, mechanical strength, and the like, by incorporation into the polymer structure one or more mesogenic moieties. Incorporation of said mesogenic moieties can lead to molecular level ordering of the polymers thereof. The present invention also provides for polymerizable mixtures containing one or more of the cyclic imino ether compositions containing one or more mesogenic moieties with, for example, one or more cyclic imino ether compositions which do not contain mesogenic moieties, epoxy resins, polymaleimides, polyamines, polyphenols or polythiophenols, polycarboxylic acids or polythiocarboxylic acids, compounds which simultaneously contain both a phenolic hydroxyl group or thiophenolic sulfhydryl group and an amino group, compounds which simultaneously contain both a phenolic hydroxyl or thiophenolic sulfhydryl group and a carboxylic acid or thiocarboxylic acid group, compounds which simultaneously contain both an amino group and a carboxylic acid or thiocarboxylic acid group in the same molecule and materials which contain one or more mesogenic moieties and an average of one cyclic imino ether group per molecule. The polymerized compositions prepared from the aforementioned polymerizable mixtures typically possess improvements in physical and mechanical properties relative to those polymerized compositions prepared using cyclic imino ether compositions which do not contain mesogenic moeities.
The term mesogen or mesogenic moiety as is used herein designates compositions containing one or more rigid rodlike structural units which have been found to favor the formation of liquid crystal phases in the case of low molar mass substances. Thus the mesogen or mesogenic moiety is that structure responsible for molecular ordering.